Modeling Snow Crystal Growth I: Rigorous Results for Packard's Digital Snowflakes

  title={Modeling Snow Crystal Growth I: Rigorous Results for Packard's Digital Snowflakes},
  author={Janko Gravner and David Griffeath},
  journal={Experimental Mathematics},
  pages={421 - 444}
Digital snowflakes are solidifying cellular automata on the triangular lattice with the property that a site having exactly one occupied neighbor always becomes occupied at the next time step. We demonstrate that each such rule fills the lattice with an asymptotic density that is independent of the initial finite set. There are some cases in which this density can be computed exactly, and others in which it can only be approximated. We also characterize when the final occupied set comes within… 

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